He said his Budget struck a balance "between tax cuts that are affordable, investments that are essential and stability that is paramount".

He rejected across-the-board tax cuts in favour of targeted help for families. The child tax credit will rise in line with earnings, giving families an extra £5 a week.

In contrast, the personal income tax allowance will rise only in line with inflation from £4,745 to £4,895 next month.

Mr Brown told MPs child benefit would rise to a maximum of £63 a week for the first child and £111 for two children.

Despite his giveaways, Budget documents show Mr Brown clawed back £265m through a clampdown on tax avoidance and increased revenue from a windfall tax on oil companies.

He also scrapped stamp duty relief for commercial property in disadvantaged areas - a measure brought in just over three years ago.

BBC political editor Andrew Marr suggested the sweeteners were not big enough to have a transforming effect on voters. But trust in Mr Brown's economic stewardship would be a central election issue, he said.

Tartan test

Mr Brown also unveiled plans for a memorial to the Queen Mother, funded through a special coin to celebrate the Queen's 80th birthday.

Other measures include equal tax status for same-sex couples and a deal with the Council of Mortgage Lenders to boost low cost home ownership.

The level where people start paying inheritance tax will also rise from £263,000 to £275,000 from April.

Mr Brown said he had met his financial "golden rule" with a £6bn surplus and he said public borrowing would continue to fall over the next five years.